1,3,-di-(isopropylideneaminooxycarbonyl) benzindazole carbamates

ABSTRACT

1-Alkylideneaminooxycarbonyl -2-alkyl or alkenylcarbonyliminobenzimidazoles or derivatives thereof such as those in which the 3-position is substituted with a carbamyl group, a carboxylic ester group or an alkylideneaminooxycarbonyl group are made and used as fungicidal agents.

United States Patent [1 1 Ahrens et al.

[ Jan. 21, 1975 l,3,-DI-(ISOPROPYLIDENEAMINOOX- YCARBONYL) BENZINDAZOLE CARBAMATES [75] Inventors: Dietrich Ahrens, Gross Flothe; Kurt Riider; Ernst Albrecht Pieroh, both of Berlin, all of Germany [73] Assignees: Scherings Ag, Berlin; Scherings AG,

Bergkamen, both of, Germany [22] Filed: Apr. 19, 1972 [21] Appl. No.: 245,644

[30] Foreign Application Priority Data May 5, 1971 Germany 2123015 [52] US. Cl 260/309.2, 260/240 G, 424/273 [51] Int. Cl C07d 49/38 [58] Field of Search 260/3092 [56] References Cited UNITED STATES PATENTS 3,541,213 ll/l970 Klopping 260/3092 3,641,048 2/1972 Dittmar 260/3092 Primary ExaminerNatalie Trousof Attorney, Agent, or FirmJoseph F. Padlon [57] ABSTRACT 6 Claims, No Drawings l.3-DI-(ISOPROPYLIDENEAMINOOXYCARBO- NYL) BENZINDAZOLE CARBAMATES The invention relates to new substituted benzimidazole carbamates, fungicidal agents containing these compounds as active substances, as well as processes for the production of these compounds.

The fungicidal action of benzimidazole derivatives is known. One of their most important representatives is the compound already introduced in the practice for the control of phytopathogenic noxious fungi. methyll-(butylcarbamoyl)-2-benzimidazole carbamatc (cf. French Patent No. 1,523,359). While this active substance exhibits a wide spectrum of action, it does not always meet the stipulated requirements, especially with respect to the control of noxious fungi in certain crop cultivations.

It has now been found that compounds ofthe general formula R1 300R 8 C R u @012 (I) wherein R and R are the same or different and represent a pos sibly monoor multi-substituted aromatic, aliphatic, or cycloaliphatic hydrocarbon radical;

R is hydrogen in addition to the aforesaid meaning; R is an aliphatic hydrocarbon radical;

R, is hydrogen, alkyl, halogen alkyl, alkoxy, halogen, or the nitro group; and

R is hydrogen or the radicals --COON C with R,, R: and R2, in the meaning of R R or R respectively, have fungicidal effect and can be used in particular for the control of phytopathogenic noxious fungi on useful plants.

In particular there should be mentioned such compounds where in the designated general formula R, and R represent a methyl radical, R, an aliphatic hydrocarbon radical with l to 4 carbon atoms, R; hydrogen, methyl, methoxy, chlorine or the nitro group, R hydro gen or the radicals -COON C(CH CONHR or COOR',,

with R and R',, in the meaning of an aliphatic hydrocarbon radical with l to 4 carbon atoms.

Other compounds within the scope of the invention are those of the formula COO N; Q/C'HJ ,1, "ca, R l -Co I -CO-Ili-R" Or COOR' wherein R,, is methyl. ethyl or allyl and R, is hydrogen, lower alkoxy, lower alkyl, halo or nitro.

The compounds according to the invention possess eminent fungicidal properties. Thus they show a good fungicidal action against numerous noxious fungi. as for example Rhizoctonia, Fusarium. true mildew fungi, Piricularia, Botrytis, Fusicladium, etc.

As the compounds are practically nontoxic and excellently tolerated by fruits and plants, they can be employed in viticulture, horticulture and the growing of ornamental plants as well as in numerous crop cultures, such as cotton, rice and the like.

Some of the compounds according to the invention show, surprisingly, an activity superior to the active substance of analogous constitution, known in the practice, against noxious fungi in important crop cultures, as for example Rhizoctonia solani on cotton.

The compounds according to the invention have the special advantage of being not only prophylactic but also curative, so that noxious fungi already established. such as Erysiphaceae, Venturia and Piricularia, cannot develop further.

Moreover, these compounds display a systemic effect, in that they are transported in the sap stream of the plants to the site of their action. The absorption of the compounds occurs not only through the leaves, but also from the soil through the roots.

According to present findings, particularly isopropylideneaminooxycarbonyl-2-t methoxycarbonylamino)-benzimidazole, isopropylideneaminooxycarbonyl-3-butylcarbamoyl- 2-( methoxycarbonyliminoJ-benzimidazole, isopropylideneaminooxy-carb'onyl-2( isopropoxycarbonylamino)-benzimidazole, isopropylidenaminooxycarbonyl 2 teth'oxycar bonylamino)-benzimidazole' and l isopropylide neaminooxyearbonyl-3-butylcarbamoyl-2- (ethoxycarbonylimino)-benzimidazole have shown ex cellent fungicidal effects.

The compounds according to the invention can therefore be used as sprays or as disinfectants in agriculture. as well as in'horticulture for the fungicidal treatment of infected or infection threatened plants and soils or for the protection of seeds.

The application can take place either with the single specific active substance alone or with the mixtures of at least two different active substances. lfdesired, other fungicides, nematocides, herbicides or otherpest control agents, dependingon thedesired purpose, may be added. Appropriately, the active substances are employed in the form of the following preparations, namely, powders, scatters,- granulations, solvents, emulsions or suspensions, with the addition of liquid and/or solid vehicles or diluents and also of wetting, adhesive, emulsifying and/or dispersing aids.

Suitable liquid vehicles used in the invention are water, mineral oils or organic solvents, such as xylene. chlorobenzene, cyclohexanol, cyclohexanone, dioxane, acetonitrile, acetic ester, dimethyl formamide, isophorone, dimethylsulfoxide. and the like. As solid vehicles that are suitable for use are lime, kaolin, chalk, talc, attaclay and other clays as well as natural or synthetic silicic .acid.

Among the surface-active substances that may be used are salts of the lignin-sulfonic acids, salts of alkyl-. ated benzenesulfonie acids, sulfonatcd acid amides and their salts, polyethoxylated amines and alcohols.

If the active substances are to be used for seed disinfection, dyes may be admixed with them. so as to give 3 the disinfected seed material a clearly visible coloration.

The proportion of active ingredient or ingredients in the agent may vary within wide limits. the exact concentration of the active substance to be used for the agent depending mainly on the quantity in which the agents are to be used for the soil or seed treatment. The agents contain between about I and 80 percent by weight, preferably between about and 50 percent by weight of active substance and approximately 99 to 20 percent by weight of liquid or solid vehicles as well as possibly up to 20 percent by weight of surface-active substances.

The new active substances of the general formula I can be produced, for example, by reacting either compounds of the general formula a. with cloroformyl oximes of the general formula C1--CO-ON=C in the presence of a diluent and of an acid acceptor or with carbamic acid chlorides of the general formula Cl CO NH R" in the presence of a diluent and of an acid acceptor or with isocyanates of the general formula OCN R" in the presence of a diluent,

e. by first exposing them to phosgene and then allowing the formed chloroformyl benzimidazoles of the general formula COCl N/ to react with oximes of the general formula 4 or their alkali salts and allowing the reaction products, if desired, to react with chloroformic acid esters of the general formula 0| with carbamic acid chlorides of the general formula (l-CO NH R in the presence of a diluent and of an acid'acceptor Or with isocyanates of the general formula OCN R" in the presence of a diluent or by first reacting compounds of the general formula m, (m, v

with chloroformyl oximes of the general formula in equimolar weight ratios in the presence of a diluent and ofan acid acceptor and then allowing them to react the chloroformic acid esters of the general formula Cl CO O R in equimolar weight ratios in the presence of a diluent and of an acid acceptor, whereupon the reaction products are, if desired, reacted with equimolar proportions of a chloroformyl oxime of the general formula c1 co o N c of a chloroformic acid ester of the general formula Cl CO O R,,,

- of a carbamic acid chloride of the general formula Cl CO NH R of an isocyanate of the general formula OCN R";-

whetfiin R", R2, R3, R4, R], R12, R g and R have the above meaning. I

The production of the compounds of the invention according to the methods (a) and (b) is carried out appropriately in an inert organic solvent, as acetone, chloroform, benzene, tetrahydrofurane 0r methylene chloride, in the presence of an acid acceptor, as triethylamine, pyridine, or a substance of alkaline reaction, such as alkali carbonate or alkali hydrogen carbonate.

According to method (c), first benzimidazole-Z- carbamate is treated with phosgene in an inert organic solvent, such as benzene, toluene, or tetrahydrofurane, and then an equimolar quantity of a tertiary amine, such as triethylamine, is added. After filtration and vacuum distillation the resulting l-chlorocarbonylbenzimidazole-2-carbamate is either isolated by treating with a hydrocarbon, such as hexane. or reacted in the same inert or another inert organic solvent either in the presence of the stoichiometric quantity of a tertiary amine or of an alkaline-reacting compound with the oxime of its alkali salt.

The preparation of the new active substances, starting with the Z-aminobenzimidazolene, is carried out cxpediently in an inert organic solvent, such as chloroform, dioxane, tetrahydrofurane, in the presence of an acid acceptor, such as triethylamine, or a substance of alkaline reaction, such sodium carbonate. At temperatures around the freezing point up to room temperature, the l-alkyleneamino-oxycarbonyl-Z-aminobenzimidazole is formed predominantly. The reaction of this compound or of the isomer mixture with chloroformic acid alkyl esters in an inert organic solvent, such Name of compound according to invention l-isopropylideneamino-oxycarbonyl-2-( methoxycarbonylamino)-benzimidaz0le 9.6 g (0.05 mole) of 2- methoxycarbonylaminobenzimidazole are admixed in ml of anhydrous chloroform with 11.65 g (0.085 mole) of acetone-oximc-O-carbonyl chloride. Into this suspension are dropped within 30 minutes 8.7 g (0.085 mole) of triethylamine in 25 ml of anhydrous chloroform while stirring. After some time a clear solution is obtained from the suspension. After treatment with active carbon, the product is shaken several times with water. After the drying of the chloroform phase with magnesium sulfate and filtration. the product is concentrated somewhat and the residue stirred into 330 ml of n-heptane. After suction filtering under vacuum, the crystals are dried at room temperature.

The yield: 10.5 g 72.5% of the theory M.p. 150- 151 C In a similar manner, when using the corresponding starting products, the following compounds can, for example, be produced:

Physical constants l. 1-|sopropylidenaminooxycarbonyl-Z-(eto xycarbonylamino)-benzimidazole M.P.: 1 10 C 2. l-lsopropylidenaminooxycarbonyl-2-( allyloxycarbonylarnino)-5methylbenzimidazole M.P.: 180 C 3. 1-lsopropylidenaminooxycarbonyl-2-( bu toxycarbonylamino)-benzimidazole M.P.: 215 C 4. l-lsopropylidenaminooxyearbonyl-2-( all yloxycarbonylamino)-5-chlorbenzimidazole M.P.: 108 110 C 5. 1-lsopropylidenaminooxycarbonyI-Zlallyloxycarbonylamino)-5-i1itrobenzimidazole M.P.: 156 C 6. l-lsopropylidenaminooxycarbonyl-2-(all yloxycarbonylamino)-5-methoxybenzimidazole M.P.: 99 100 C 7. 1-lsopropylidenaminooxyearbonyl-2-(isopropoxycarbonylamino)-benzimidazole M.P.: 96 98 C 8. l-lsopropylidenaminooxycarbonyl-2-(methoxycarbonylamino)-5-chlorbenzimidazole M.P.: 129 130 C 9. I -lsopropylidenaminooxycarbonyl-2-( isobutoxycarbonylamino)-benzimidazole M.P.: 250 C 10. 1 -Isopropylidenaminooxycarbonyl-2-(ethoxycarbonylamino)-5-methylbenzimidazole M.P.: l 14 1 15 C t]. l-lsopropylidenaminooxycarbonyl-2-(methoxycarbonylamino)-5-methoxybenzimidazole M.P.: 130 C 12. l-lsopropylidenaminoxycarbonyl-2-(etho xycarbonylamino)-5-chlorbenzimidazole M.P.: 129 130 C 13. l-( Diphenylmethylidenaminoxycarbonyl )-2- (methoxycarbonylamino)-benzimidazole M.P.: 151 C 14. 1 (methylphenylmethylidenaminooxycarbonyl 2-)methoxycarbonylamino)-benzimidazole M.P.: I43 144 C 15. l-(Diphenylmethylidenaminooxyearbonyl )-2- (isopropoxycarbonylamino)-benzimidazole M.P.: 156 157 C as acetone, chloroform, or benzene, in the presence of a basic substance, such as triethylamine or sodium carbonate, leads to 1,3- and 1.2-disubstituted substances.

The derivatives of the general formula (I). trisubstituted in l-. 2- and 3 position, can be obtained by further reaction of the 1,2-derivatives with chloroformic acid esters or carbamic acid chlorides in an inert solvent and in the presence ofan acid acceptor or by reaction with an isocyanate in an inert organic solvent. The new active substances of the general formula I may, if R represents hydrogen, be present also in a tautomeric form.

The following illustrate the production of the new hcn/imidazole earhamates l.3-di-( isopropylideneaminooxycarbonyl j-Z- (methoxycarbonylimino )-5-methoxybenzimidazole 11.05 g (0.05 mole) of 5-methoxy-2-(methoxycar bonylaminol-benzimidazole are admixed in 40 ml of anhydrous chloroform with 24 g (0.18 mole) of and concentrated after filtration. The oil is taken up in a little ether and caused to crystallize by intensive cooling.

The yield: 12.7 g 60.6% of the theory M.p. 168 169 C Similarly, there can be produced:

Name of compound according to invention Physical constants concentrated under vacuum at 20 C. The oily residue is brought to crystallization with a little ether.

The yield: 35.7 g 75% of the theory M.p. 260 C By this method also the following compounds can be produced:

l,3-di-( isopropylideneaminooxyca rbonyl )-2- (methoxycarbonylimino )-benzimidazole M.P.: 132 C 1,3-di-( isopropylideneaminooxyearbonyl )-2- (ethoxycarbonyl-imino )-benzimidazole l,3-cli-( isopropylideneaminooxycarbonyl )-2- (allyloxycarbonylimino )--methoxybenzimidazole 1,3-di-( isopropylideneaminooxycarbonyl )-2- (allyloxycarbonylimino)-5-methylbenzimidazole M.P.: 184 C M.P.: 130- 131C M.P.: I63 164 C l-isopropylideneaminooxycarbonyl-S-allylcarbamoyl- 2-( ethoxycarbonylimino)-benzimidazo1e 8.0 g (0.0263 mole) of lisopropylideneaminooxycarbonyl-2-(ethoxy)- benzimidazole in 100 ml of anhydrous chloroform are stirred at room temperature with 2.3 g (0.0277 mole) of allylisocyanate until a clear or almost clear solution is formed. After filtration, chloroform is evaporated under vacuum and the residue brought to crystallization by taking up in little ether and intensive cooling.

The yield: 9.8 g 95.8% of the theory M.p. 196 198 C l-isopropylideneaminooxycarbonyl-3-nbutylcarbamoyl-2-( methoxycarbonylimino benzimidazole To a solution of 35.5 g (0.122 mole) of lisopropylideneaminooxycarbonyl-2-( methoxycarbonylamino)-benzimidazole in 450 ml of absolute chloroform there is added in drops within minutes at room temperature while stirring a solution of 12.8 g (0.129 mole) of n-butylisocyanate in 50 ml of absolute chloroform. Then 3 ml of triethylamine are added. The reaction mixture is left standing over night and then Physical constants Name of compound according to invention l-isopropylidencaminooxycurhonyl-fl-hutylcurhnmoyl-Z-t methtmycurhonylimino henlimiduzole 460" l-istipropylidcncan1iinat xycarhonyI-3-ethyl carhamoyl-2-( a]lyloxycurhonylimino )-4- methylbcnzimidazolc 26U C l-isopropylidcneaminot xycarhonyl-3-hutylcarbamoyl-2-(allyloxycarhonylimmo1-5- mcthylbenzimidazolc 183 C l-isoprtipylidcneaminm)xycarhonyl-fl-butyl curbamoyl-24 cthoxycarbonylimino hcnzimidazole l-isopropylidcncaminooxycarhonyl-3-hutylcarhamoyll allylt xycarhonylimino )-5- chlorohenlimidazolc The new compounds are soluble in organic solvents, such as acetone, isophorone, chloroform, dimethylformamide, tetrahydrofurane, dioxane, acetic acid ethyl ester, cyclohexane, and the like.

The starting products for the production of the compounds according to the invention are known in the art or can be produced by known methods.

From the following examples the fungicidal action of the compounds of the invention as compared with known agents will become evident.

Example 1 Cotton seeds disinfected with 50% formulations were seeded in a compost soil infected with Rhizoctonia solani, grains for each concentration. After a cultivation time of two weeks at a temperature of 25 to 27 C, the number of sound cotton seedlings was deter mined.

Compounds according to invention sound plants from seeding after two weeks cultivation time carbamoyl-Z-(ethoxycarbonylimino )-benzimidazole Continued Compounds according to invention sound plants from seeding after two weeks cultivation time 2.0 gn active subsL/kg seed 5. l-iso ropylideneaminooxycarbonyl-2- (met oxycarbonylamino)-benzimidazole 71.3

6. l-isopropylideneaminooxycarbonyl-Z-(ethoxycarbonylamino)-benzimidazole 59.3 Reference agents Methyl-Hbutylcarbamoyl)-2-benzimidazole carbamate 64.6

N -(trichloromethyl-thio)-cyclohex-4-enel Z-dicarboximide 50.6

Steamed soil, seed material not heated 91.3

Infected soil. seed material not heated 14.5

Example 2 plant. and a root analysis after a cultivation time of-l9 days at a temperature of 22 to 25 C. Root analysis:

4 white roots, without fungus necroses 3 white roots. slight fungus necroses brown roots. greater fungus necroscs severe fungus necroses, roots rotted The test resultsprove the superior effect of the compounds according to the invention against Rhizoctonia solani in comparison with commercial preparations.

25 Example 3 Compounds according to invention Mg act. Subst No. sound Fresh Root per liter of peas after Plant Anal. 19 days wt. (g) (1-4) 1. l-lsopropylidenaminooxycarbonyl-2- l0 mg 12 8 g 3 isopropoxycarbonylamino)-benzimidazole 20 mg 24 I9 g 4 40 mg 24 19 g 4 2. l-lsopropylidenaminooxycarbonyl-3- 10 mg 2 l butylcarbamoyl-2-(ethoxycarbonylimino) 20 mg 22 g 4 benzimidazole 40 mg 24 16 g 4 3. l-lsopropylidenaminooxycarbonyl-3- 10 mg l l allylcarbamoyl-2-(ethoxycarbonylimino)- mg 18 l l g 4 benzimidazole 40 mg 15 g 4 4. l-lsopropylidenaminooxycarbonyl-2- l0 mg 16 l l g 2 (methoxycarbonylamino)-benzimidazole 20 mg 23 [5 g 3 mg 25 l7 g 4 5. l-lsopropylidenaminooxycarbonyl-2-(ethoxy- 10 mg l2 10 g .3 carbonylamino)-benzimidazole 20 mg l9 16 g 4 40 mg 20 l6 g 4 6. l-lsopropylidenaminooxycarbonyl-3- l0 mg 23 20 g 4 butylcarbamoyl-2-(methoxycarbonylimino)- 20 mg 24 I9 g 4 benzimidazole 40 mg 24 20 g v 4 Reference agents l.4-dichloro-2.S-dimethoxybenzene l0 mg 5 3 g l 20 mg 12 9 g 3 40 mg 17 I2 g 4 N(trichlormethylthio)-cyelohex-4- 10 mg 2 l g l en-l ,Z-dicarboximide 20 mg l l 6 g l' 40 mg ll 6 g. I

Steamed soil 24 13 g 4 Infected soil 0 l Compounds according to invention mg of active l -1o. of subst. per infected liter of plants after soil 4 weeks I. l-isopropylideneaminoqxycarbonyl-2- 20 mg (isopropoxycarbonylammo)-benztmtdazole 30 mg 0 z. l-isopropylideneaminooxycarbonyl-Z- mg 0 (methoxycarbonylamino)-benzimidazole 30 mg 0 3. l-isopropylideneaminooxycarbonyl-Z- 20 mg 0 (ethoxycarbonylamino)-benzimidazole 30 mg 0 4. l isopropylideneaminooxycarbonyl-3- 20 mg butylcarbamoyl-2-(methoxycarbonylimino)-b en2imidaz0le 30 mg Reference Agent 5. N-( trichloromethylthio )-cyclohex-4- 20 mg 6 ene-l ,Z-dicarboximide 30 mg 6 Steamed soil 0 Untreated soil 6 Example 4 The testing of the action against True Mildew [iavsip/ze cic/mraceurum on pumpkin (Cucu-rbila pepo var. gimnmntiina) was done on young plants with two fully developed foliage leaves. The plants were sprayed dripping wet with the agents on the top and underside of the leaves. One day later the plants were infected with the mildew spores. Seven days later the degree of infection was determined according to the degree of coverage on the top of the leaf with the fungus turf (percent of infection of the leaves).

Compounds according to invention 250 ppm ppm '/1 of infection Compounds according to invention of the leaves after 8 days 45 ppm l-isopropylideneaminooxycarhonyl-Z- (methoxycarhonylamino)-benzimidazole l-isopropylidcneaminooxycarhonyl 2- (ethoxycarbonylamino)-benzimidazole l l Reference agent (6-( l-methyl-hcptyl)-2.4-dinitrophcnyl )-crotonate I00 control (untreated) Ill!) of infection of the leaves [0 ppm 2 ppm 1 l-isopropylideneaminooxycarbon yl-2-( methoxyearbonylamino )-benzimidazole 2. l-isopropylideneaminooxycarbonyl-Z-(isoproxyearbonylamino)-benzimidazole 3. l-isopropylideneaminooxycarbonyl-3-butylcarbamoyl-2- (ethoxycarbonylimino)- benzimidazole Reference agent 4. Methyl-l-(butylcarbamoyl)- Z-benzimidazole carbamate Control (untreated) Example 5 Leaf stems of pumpkin plants (Cucurhila pepo var. griunwntiina) were treated with the compounds as follows. A cotton wad was placed midway on the leaf stem between the stem insertion and the start of the leaf which wad had been imbided with 2 ml of a suspension containing 45 ppm of the compounds to be tested. To prevent evaporation, the wad was wrapped in plastic foil. On the same day the leaves were dusted with the spores of pumpkin mildew (Erysiphe cichoracearum). The evaluation according to the percentage infection of the leaf area with the fungus turf was made 8 days later. The systemic fungicidal effect due to translocation of the compounds of the invention in the plant is demonstrated by the test data listed in the following table.

Example 6 Rice plants were sprayed with the substances to be tested about two weeks after seeding. On the following day the plants were infected artificially with a suspension of about 200,000 spores per ml of Piricularia uryzae (rice blast). The infection was carried out by suspending the spores, grown on a synthetic culture medium, in an aqueous solution of 0.05% sodium oleate and 0.2% gelatin and spraying on the treated plants. After keeping the test plants for 5 days in an infection chamber at about 26 C and almost relative humidity, the percentage infection of the leaves was evaluated and set in relation to the infection of the control (relative percent).

% of infection 200 ppm 40 ppm l. I -isopropylideneaminoox yearbonyl- 2 methoxycarbonylamino)'benzimidazole l-isopropylideneaminooxlycarbonyl- Z-butylcarbamoyl-Z-(met oxycarbon ylimino )-benzimid azole l-isopropylideneaminooxycarbonyl) -2-( isopropoxycarbonylimino)- benzimidazole l'isopropylideneaminooxycarbonyl 3-(allylcarbamoyl )-2-ethoxycarbonylimino-benzimidazole iooo pp 2000 Reference agent ppm 5. N-(trichloro-methyl-thio)- cyclohex-l-ene- I ,2-dicarboximide Control (untreated) Example 7 good systemic effect of the compounds according to the invention on the plant parts above ground when the Rice seeds were placed in soil which had been thor- 25 agents had been worked into the soil.

Compounds according to invention of infection (relative) 1-isopropylideneaminooxycarbonyl-2- Control (untreated) I00 (absolute 60%) oughly mixed with 25 ppm of the compounds to be tested. After about 2 weeks, the rice plants developing in this soil were infected with a suspension of about 200,000 spores per ml of the causative agent of rice blast (Piricularia oryzae) in an aqueous solution of 0.05% sodium oleate and 0.2% gelatin. The plants were then kept 5 days in an infection chamber at 26 C and a relative humidity of almost 100%. After this time the percentage infection of the leaves was evaluated and set in relation to the leaf infection of the control plants (relative percent). From this example can be seen the Compounds according to invention of infection 10 5 2 1 p p pp pp 1 l-isopropylideneaminooxycarbonyl- 2-(methoxycarbonylamino)-benzimidazole 0 0 0 3.2

2. l-isopropylideneaminoox ycarbonyl- 2-(ethoxycarbonylamino)- benzimidazole O 0 0.2 4

3. l-isopropyliden'eaminooxycarbonyl- 3butylcarbamoyl-2-(methoxycarbonylimino)-benzimidazole 0 0 0.2 l

4. l-isopropylideneam inoox ycarbonyl- 2-(isopropoxycarbonylamino)- benzimidazole 0 0.2 I4 50 5. l-isopropylideneaminooxycarbonyl- 2-(methoxycarbonylamino)-5- methoxy-benzimidazole 0 6 67 98 6. l-isopropylideneaminooxycarbonyl- 3-butylcarbamoyl-2-(ethoxycarbonylimino)-ben2imidazole 0 0 0 l8 (ontinucd Compounds according to invention of infection 5 2 Control (untreated) It) 1 pp PP"'' PP'" pp 7 l-isopropylideneaminooxycarbonyl- 3-allylcarbamoyl 2-(ethoxycarbonylimono)-benzimidazole O O 3 Reference agent 138 ppm 69 ppm 35 ppm 8. methoxyethyl-Hg-silicate l 8 I00 16 Example 9 The fungicidal effect of compounds according to the invention against plant-pathogenic fungi was tested on synthetic culture media in Petri dishes, (agar impregnation test). A culture medium consisting of 2% malt extract and 1.5% agar-agar powder was sterilized and thoroughly mixed before solidification with the compounds to be tested, so that the culture medium contained the active substances listed in the table in differ- Compounds according to invention Botrytis Cinerea 10 l PP pp 1. l-lsopropylideneaminooxycarbonyl- 2-( methoxycarbonylamino benzimidazole 2. l-lsopropylideneaminooxycarbonyl- 2-(ethoxycarbonylamino)- benzimidazole 83 3. l,3-Di-(isopropylideneaminooxycarbonyl-2-(methoxycarbonylimino)-benzimidazole 63 4. l-lsopropylideneaminooxycarbonyl 3-butylcarbamoyl-2-(methoxycarbonylimino)-benzimidazole l0. l-lsopropylideneaminooxycarbonyl- 2-(isobutoxycarbonylamino)- benzimidazole l l. l-lsopropylideneaminooxycarbonyl- 1 2(ethoxycarhonylamino)-5- methylbenzimidazole l2. l-lsopropylideneaminooxycarbonyl- 2-( methoxycarbonylamino)-- methoxybe nzimidazole l3. l-Isopropylideneaminooxycarbonyl Z-(ethoxycarbonylamino)-5- chlorbenzimidazole Reference agent N-( trichloro-methyl-thio )-cyclohe x- 4-ene-l ,2-dicarboximide 8 Control (untreated) 0.01 V Ppp p pp ent quantities of 10, l. 0.1 and ().()l ppm. The culture medium was, after its solidification, inoculated with a platinum dropper containing each time about 100 spores of the fungi to be tested. After exposure for 5 to days at 22 C, the diameters of the fungus colonies were measured in mm. The diameter of the colonies on untreated culture media (control) was taken as 100 and set in relation to the diameter of the colonies on the treated culture media (relative percent).

Diameter of the fungus colonies in mm (Relative percent at control 100) Fusicladium dendtriticum l0 1 0.1

Piricularia 10 l 0.1, pp ppm pp Example Young pumpkin plants with fully developed cotyledons, grown in normal humus soil, were used for the Compounds according to invention chalk, dye, oil, and the like. Then the seed was put in soil and was exposed to a temperature of 6 to 12 C in an airconditioned chamber. After 4 weeks the percentual infection of the diseased plants was determined.

% of infection tests. After the roots had been freed from the adhering soil in water, two plants each were placed in aqueous suspensions of ppm of each of the substances to be tested. The young plants stood in the suspensions only to such a depth that the roots and a piece of the stem, hypocotyl portion, at most 5 mm long were immersed in the liquid. After 7 and 24 hours, respectively, the plants were taken out and the plant parts which had come in contact with the suspensions were rinsed off in water. Then the plants were sterilized externally with a l/( solution of sodium hypochlorite. From the upper end of the about 40 mm long hypocotyl, directly under 2 ppm 1 ppm 0.5 ppm l-(diphenylmethylideneaminooxycarbonyl)- 2-(methoxycarbonylamino)-benzimidazole 0.4 3 36 t l-(methylphenylmethylideneaminooxycarbonyl)-2-(methoxycarbonylamino)- benzimidazole 0 0 l6 l-(diphenylmethylideneaminoxycarbonyl- 2-(isopropoxycarbonylamino)-benzimidazole 0 l 20 Control (untreated) I00 We claim: I. A compound of the formula: 20

Q0 0 N= I N at,

R, N -N-c o 0 [L di 3 C, e 0 N= 0 a wherein R is methyl, ethyl or allyl and R is hydrogen, lower alkoxy, lower alkyl halo or nitro.

the insertion of the cotyledons, a piece of stem about 3 mm long was cut out. The stem pieces were placed in sterile Petri dishes with the cut area on a malt extract-agar (2% malt extract and 1.571 agar-agar powder), which had been well mixed before cooling with spores of Botrytis cinerea. Two days after the laying out of the stem pieces the inhibition coronae, no growth of Botrytis, formed around the stem pieces were determined as to their diameter. The size of the inhibition coronae reflects the velocity of the conductivity and the intensity of the effect.

Compounds according to invention Diameters 2. A compound of the formula set forth in claim 1 which is l,3-di-(isopropylideneaminooxycarbonyl)-2- (methoxycarbonylimino) 5-methoxybenzimidazole.

3. A compound of the formula set forth in claim I which is l.3-di-(isopropylideneaminooxycarbonyl)-2- (methoxycarbonylimino )-benzimidazole.

4. A compound of the formula set forth in claim 1 which is l.3-di-(isopropylideneaminooxycarbonylJ-2- (ethoxycarbonylimino)-benzimidazole.

5. A compound of the formula set forth in claim 1 inhibition coronae in mm after action of 20 ppm suspensions during a period of 7 hours 24 hours I l-Isopropylideneaminooxycarbonyl-Z- (methoxyearbonylamino)-benzimidazole 29 34 2. l-lsopropylideneaminooxycarbonyli- (ethoxycarbonylamino)-benzimidazole 2 l 23 3. I ,3-Di-( isopropylideneaminooxycarbonyl)-2-(methoxycarbonylimino)- benzimidazole l9 l8 4. l-lsopropylideneaminooxycarbonyl- 3-(butylcarbamoyl)-2-methoxycarbonylimino )-benzimidazole 24 31 5 l-lsopropylideneaminooxycarbonyl- 2-(isopropoxycarbonylamino)- benzimidazole 14 22 Reference agent Methyll -(butylcarbamoyl )-2- benzirnidazole-carbamate l3 16 Control (untreated) 0 0 Example l l I I which is l,3-di-(isopropyleneaminooxycarbonyl)-2- Rye seed naturally infected with Fusariimi "it'd/L was thoroughly mixed withthe substances to be tested. To obtain a homogeneous distribution of the active substance on the grain, the compounds to be tested were provided with the usual additions, such as kaolin. talc.

(allyloxycarbonylimino)-S-methoxybenzimidazole.

6. A compound of the formula set forth in claim I which is l,3-di-(isopropylideneaminooxycarbonyl)-2- (allyloxyc arbonylimino )-5-methylbenzimidazole. 

2. A compound of the formula set forth in claim 1 whicH is 1, 3-di-(isopropylideneaminooxycarbonyl)-2-(methoxycarbonylimino)-5 -methoxybenzimidazole.
 3. A compound of the formula set forth in claim 1 which is 1,3-di-(isopropylideneaminooxycarbonyl)-2-(methoxycarbonylimino) -benzimidazole.
 4. A compound of the formula set forth in claim 1 which is 1,3-di-(isopropylideneaminooxycarbonyl)-2-(ethoxycarbonylimino) -benzimidazole.
 5. A compound of the formula set forth in claim 1 which is 1,3-di-(isopropyleneaminooxycarbonyl)-2-(allyloxycarbonylimino)-5 -methoxybenzimidazole.
 6. A compound of the formula set forth in claim 1 which is 1,3-di-(isopropylideneaminooxycarbonyl)-2-(allyloxycarbonylimino)-5 -methylbenzimidazole. 